1. Field of the Invention
The present invention relates to the field of valves for controlling fluid flow and more particularly a valve apparatus for controlling flow into a branch conduit of a fluid distribution network.
2. Background
U.S. Pat. No. 631,699 to Darragh, et al discloses a conventional gate-type or, alternately, a globe-type valve for controlling flow of fluid. The conventional two-way gate-type valve housing forms a portion of a fluid containing conduit providing a straight through flow path between axially aligned inlet and outlet openings or ports. The hollow housing includes an internal flow cavity communicating the two housing flow openings. The gate-type flow closure element is disposed in the flow cavity and reciprocated or shifted between the open and closed positions by manual rotation of a helically threaded stem or shaft. The valve stem extends through a releasable valve bonnet that closes the housing cavity and which carries packing to prevent leakage between the stem and bonnet. Side ports or openings are provided in the disclosed valve housing to enable use as a three or four way valve, if desired, or to enable repid change of the gate member when appropriate. When the closure member is moved to the lower closed position fixed seat or port carried by the housing, all flow through the valve is terminated.
U.S. Pat. No. 825,064 to Levey discloses a valve apparatus having two inlets and a single outlet. Reciprocating movement of the gate like flow control element effect by stem movement selects one of the two inlets for communicating with the outlet while blocking flow through the other outlet. The Levy apparatus serves as a diverter or flow switching device rather than as an on-off valve.
U.S. Pat. No. 1,190,698 to King discloses a valve apparatus having a rotatable stem employing a helical thread arrangement to reciprocably move a flow closure element that is used in well drilling operations as a blowout preventer. When the closure is shifted into the open position, all three housing flow ports are placed in flow communication. When the flow closure element is shifted to the close position, straight through vertical flow is blocked and flow from the lower vertical opening is diverted into the horizontal Tee-branch. The disclosed apparatus cannot be employed to isolate the horizontal flow opening from either vertical opening or the straight through vertical drilling passageway.
U.S. Pat. No. 3,033,515 to Brisbane disclosures a reotatable plug valve operably disposed in a three-way flow valve housing in FIG. 5-8. The ported rotatable plug flow closure element enables a straight through flow path or passage or between the axially aligned flow openings, but which arrangement greatly increases the size, weight and cost of the valve. In addition, a powerful actuator is requird to assist an operator to manipulate the closure element between operating positions in all but the smallest sizes. Such actuator requirement further increases the size and cost of the valve apparatus.
U.S. Pat. No. 3,068,901 is entitled "Three Way Gate Valve". The expandable gate member is positioned to select which of the two valve housing outlet ports the flow will be diverted through. while providing a direct full open and unobstructed straight direct flow passageway in one condition, the other operating condition of the gate closes that direct flow path for directing all flow at a right angle.
In U.S. Pat. No. 3,771,561 to Santamaria, an outlet conduit selective flow control apparatus is disclosed for directing flow from a common or supply inlet through one of two outlet openings. A reciprocating slide or gate is shifted to control or select the outlet opening forming the desired flow path.
Curran U.S. Pat. No. 3,771,562 discloses a three way valve suitable for both flow divergence (separation) or convergence (mixing). Two side ports and a bottom port are provided by the three way valve housing. No straight through path between the side ports is provided. The bottom port is arranged to continuously communicate or connect with either one or both side ports. A pressure balance reciprocating sleeve serves as a flow blocking member to control the desired flow path.
U.S. Pat. No. 4,327,772 disclosed a three ported or three way valve housing having a shiftable closure element for selectively diverting flow through one of the two outlets. No unrestricted straight through flow path is provided in either operating condition.
Each of the forgoing patents is hereby totally incorporated by this specific reference for forming a portion of this disclosure as if the contents of each were fully set forth herein.